Golf shoe with a stabilizing system

ABSTRACT

A golf shoe has a stabilizing system consisting of an upper, a longitudinally extending midsole consisting of polyurethane, and a shank, wherein the midsole additionally to its longitudinal extension is extended vertically with a medial arch support structure, a lateral side support structure and a heel support structure. The structures are bonded to the outside of the upper and the medial arch support structure and the lateral side support structure extends upwardly and encircles eyelets for lacing of said upper. In order to further stabilize the golf shoe through all the phases of the swing of a golfer, the heel support structure ( 9 ) of said midsole ( 2 ) extends vertically to a point above the human calcaneus of a wearer, approximately to the point where the Achilles tendon is fixated. Midsole beams ( 14,23 ) are extending from the vertically extending heel support structure towards the vertical medial ( 8 ) and lateral ( 7 ) support structures.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is entitled to the benefit of and incorporates by reference essential subject matter disclosed in International Patent Application No. PCT/DK2009/000154 filed on Jun. 24, 2009 and Danish Patent Application No. PA 2008 00961 filed on Jul. 8, 2008.

TECHNICAL FIELD

The invention concerns a golf shoe with a stabilizing system.

BACKGROUND OF THE INVENTION

Stabilization of the golf shoe is needed during the swing phase for mainly two reasons. First, if the shoe is unstable due to a sole with a poor grip or a weak upper, injuries to the ankle in the form of sprain may occur in the follow-through phase, i.e. the part of the swing phase where the right handed golfer has hit the ball and is rotating his body and right leg and foot. Second, with a sufficiently stabilized footing, the golfer can concentrate on other parameters than footing to improve his golfing performance. The need for stabilization of golf shoes has been recognized in the golf world for a long time. A typical way of stabilizing such shoe is to reinforce the upper with an additional material, typically a piece of textile sewn onto the upper on the medial and lateral side in the area of the midfoot. In this way the extra piece of textile adds stiffness to the golf shoe. Another known solution is described in JP 2005021384A2, where the sole of a golf shoe is extended vertically on the inner side of the shoe along the full longitudinal length of the sole. While both solutions contribute to improving stabilization, they suffer from drawbacks. Sewing additional textiles to the upper is, although giving an opportunity for aesthetic creations, an additional manufacturing step which adds cost to the manufacturing process. Further, the solution described in JP 2005021384A2 only provides partly stabilisation during the swing. In a known manner, the swing phase can be divided into five phases, namely addressing, backswing, downswing, impact and follow-through. The solution in JP 2005021384A2 will increase stabilisation in the downswing and impact phases, but not in the backswing phase, where the golfer after addressing the ball is raising the club to its highest point and preparing for the downswing. Another stabilizing solution is known from U.S. Pat. No. 5,678,329, and concerns an athletic shoe, which has a polyurethane midsole with left and right side upwardly extending portions. The portions are encircling eyelets of the shoe, and the shoe lace is guided through the eyelets. During the rotational movement of the body through the swing phases, especially in the follow-through phase where the wrist of the foot rotates, there is exerted a rotational force on the shoe which force the concept taught in U.S. Pat. No. 5,678,329 cannot fully handle.

SUMMARY OF THE INVENTION

The current invention solves the problem of providing a stabilization system for a golf shoe, which system provides improved stabilisation in all phases of the swing.

The problem is solved with a stabilization system according to the characterising part of claim 1. This system stabilises and supports the midfoot during the golfswing, hereby increasing the swing power of the golfer. In order to support the foot in all five phases of the golf swing, the polyurethane (PU) midsole is extended vertically on the upper in three selected positions, namely on the outside of the upper on the medial arch, on the lateral side of the foot and in the heel area. In combination, these three vertical support structures, which are integrally moulded with the rest of the PU midsole, provide encapsulation of the foot and increased stability, because they are tightly bonded to the upper of the shoe. Bonding takes place during the PU injection process. PU has a larger stiffness than textile, and the stiffness in the three support structures can be customized by varying the thickness of the PU. The thicker the PU, the more stiff the shoe. A further inventive stabilizing measure is to connect the medial and lateral support structures through respective lateral and medial beams to the vertically extending heel support. This provides additional support and stabilization especially during the backswing, impact and follow-through phases of the swing. The three support structures are extended vertically to a height corresponding to the position of the eyelets on the upper, preferably to the eyelets placed closest to the ankle. In this way the midsole embraces and supports more of the foot than the design of U.S. Pat. No. 5,678,329, where the upwardly extending portions only extend to ⅔ of the distance between the bottom surface of the outsole and the lace openings. The heel support structure according to the present invention extends vertically to a point above the calcaneus of a wearer, and the PU of the arch support structure and the lateral side support structure encircles one or more eyelets. As the support structures follow the shape of the upper, they are inclined towards the lacing area, and exert bending force already from manufacturing. This bending force gives an improved grip between shoe and foot, and contributes to keeping the shape of the shoe over time. When pulling the lace, the medial and lateral support structures are moved towards each other, and this has the effect that an even better grip around the foot is achieved once the golfer has laced his shoe.

Advantageously, also the medial arch support structure and the lateral side support structure are formed by beams.

Preferredly, the beams delimit one or more windows which are devoid of midsole material. In order to increase stability, the free space between the beams can be filled with midsole PU, but this adds to the weight of the shoe. It has been found sufficient for stabilization purposes to have single beams of PU being bonded to the upper. This has the advantage, that the midsole can be kept lightweight.

Further stabilization is achieved if each structure is formed by beams defining an essentially triangular shape of the structure which has a window devoid of midsole material. As is well known in mechanical and construction engineering, triangles add structural strength to a construction.

Conventionally, a shank is placed in the midsole or between midsole and outsole. It has been found, that increased stability is achieved by using a double shank system, i.e. a first shank fully or partly integrated in the midsole, and a second shank placed between the midsole and the outsole. The second shank is close to the green during addressing, backswing and downswing, while the first shank in the midsole provides stability during impact and follow-through.

A particularly good stabilization is achieved, where the two shanks overlap each other in an area of the midsole, which area corresponds to the longitudinal position of the encircled eyelets. The toe ends of the shanks are sandwiching the midsole in a place corresponding essentially to the position where the vertically extending beams of the medial and lateral support structures are placed. The first shank in the midsole is surrounded by the three vertically extending support structures.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is now described in detail by way of the drawings in which:

FIG. 1 is a side view of the inventive golf shoe;

FIG. 2 is a perspective view of the midsole and outsole used in the inventive shoe; and

FIG. 3 is a rear view of the midsole and outsole used in the inventive shoe.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a lateral view of a golf shoe 1 according to the invention. A polyurethane (PU) midsole 2 is bonded to a shoe upper 3. Such upper can be made of textile or leather. In a known manner, spikes 4 screwed into the outsole 5 provide good grip to the green. The outsole 5 and 6 is made of hard density thermoplastic polyurethane (TPU), which is bonded to the midsole 2. A shank 20 is placed between the midsole and the TPU outsole, which outsole is thin in the midfoot area. This shank is made of carbon fibres and has a good torsional stiffness. On the upper, the lateral side support structure 7 extends vertically and follows the shape of the upper. Beam 10 originates in the longitudinally extending portion of the midsole, and is connected to beam 12 via cross beam 11. As seen in FIG. 1, the beams are essentially rectangular, thus having rectilinear sections between the structures or portions they connect. The beams are tapered in a direction towards the top of the beam, which top therefore has a smaller surface than the base portion of a beam, which is the portion bonded to the upper. Beams 10, 11 and 12 are cast in one piece, integrally injection moulded with the longitudinally extending midsole. More specifically, manufacturing is made by first roughening the upper 3 before PU injection on the places, where beams 10, 11, 12 and 14 as well as vertical heel support structure 9 are to be bonded. This is a pretreatment of the upper, and typically done by a mechanical roughening machine. After roughening, the upper is put on a last, and the last is placed in a mould. Inside the mould, TPU outsole 5, 6 is already placed or can be injected afterwards. Then PU is injected, and flows in the mould to the roughened places of the upper, and bonds instantaneously and tightly to the upper.

Midsole 2 is in the preferred embodiment made of light polyurethane (PU) material, also called PU light, based on polyester. PU light is a known variant of PU, and has a low density (0.35 g/cm³), i.e. is a lightweight material. A further characteristic is good shock absorbing properties. Shore A hardness is between 38 and 40.

The lateral side support structure 7 is extended vertically to the area, where laces 17 are placed. The support structure encircles two eyelets 18 and 19 with PU cross beam 11. Alternatively, only or also eyelet 21 could be encircled. More beams can be added to provide further stability and stiffness of the shoe. Alternatively window 15, delimited by midsole portion 13, can be filled with PU, but preferably having a lower thickness than the beams 10, 11 and 12. According to the invention an additional beam 14 connects the lateral side support structure 7 with the vertical heel support structure 9, hereby creating a further window 16, and a medial beam 23 connects materially the medial support structure 8 with the heel support structure. FIG. 3 gives a view of the heel support structure 9 from the rear. The vertically extending heel support structure extends to a point above the human calcaneus, approximately to the point where the Achilles' tendon is fixated. This results in a firm heel grip. It will be seen from FIG. 3 that support structures 7 and 8 extend slightly above heel 9.

FIG. 2 shows in perspective the midsole 2 used in the inventive shoe. A dual shank system provides extra stability of the shoe. Shank 22 consists of a mixture of thermoplastic polyethylene (TPE) and nylon and is preferably placed in the top of midsole 2, recessed into the surface. It extends in longitudinal direction from the heel area to the position, which corresponds to placement of eyelets 18 and 19. Further stabilization is provided by shank 20 placed underneath the midsole. Shank 20 is made of carbon fibre and reinforced with nylon.

The scales of the inventive shoe can be varied. In a preferred embodiment, the beams 12 and 10 measure 75 millimetres (mm) and 65 mm in length respectively, and have a thickness of 3 mm. The full height A-A of heel 9 in FIG. 2 is 80 mm.

The described embodiments can be combined in different ways. 

1. A golf shoe with a stabilizing system, the shoe having an upper, a longitudinally extending midsole consisting of polyurethane, and a shank, wherein the midsole additionally to its longitudinal extension is extended vertically with a medial arch support structure and a lateral side support structure, said structures being bonded to the outside of the upper and the medial arch support structure and the lateral side support structure extending upwardly to and encircling eyelets in the shaft wherein a heel support structure of said midsole extends vertically to a point above the calcaneus of a wearer and that, respectively, a lateral beam and a medial beam of the midsole is extending from the vertically extending heel support structure towards the vertical medial and lateral support structures.
 2. The golf shoe according to claim 1 wherein said medial and lateral support structures are formed by beams extending from the longitudinally extending midsole and upwards.
 3. The golf shoe according to claim 2 wherein the beams delimit one or more windows devoid of midsole material.
 4. The golf shoe according to claim 3, wherein said one or more windows have an essentially triangular shape.
 5. The golf shoe according to 2, wherein the shank is fully or partly embedded in the midsole, and a second shank is placed between an outsole and the midsole.
 6. The golf shoe according to claim 5 wherein said two shanks overlap each other in an area of the midsole corresponding to the longitudinal position of the encircled eyelets. 